LP-719 Rev. 000 Rel. 000 Date 6.25.20
8
I. High Elevation Installations
WARNING
!
Natural gas at high elevation might contain less heating value than
the typical 1,000 BTU/cu ft and therefore can cause an improper
air / gas mixture leading to improper combustion. For natural gas
installations above 3,000 ft, call your gas provider to determine
the heating value of the supplied natural gas.
H. Water Temperature Adjustment and Scalding
This boiler can deliver
scalding water. Be careful
whenever using hot water
to avoid scalding injury.
Certain appliances such as
dishwashers and automatic
clothes washers may
require increased water
temperatures. By setting the
thermostat on this boiler to
obtain the increased water
temperature required by
these appliances you may
create the potential for scald
injury.
To protect against injury,
install a mixing valve in the
water system. This valve
will reduce point of use
discharge temperatures by
mixing cold and hot water
in branch supply lines. Such
valves are available from
your local plumbing supplier.
Table 3 details the
relationship of water
temperature and time with regard to scald injury and may be used
as a guide in determining the safest water temperature for your
applications.
On ELU-150WBN / ELU-199WBN Models ONLY
If the boiler is to be used only in Heating Mode (not connected
to an indirect water heater), the electrical connection of the
3-way valve motor MUST BE DISCONNECTED while the boiler is
operating in central heating mode. This will lock the valve motor
in central heating mode and ensure freeze protection operates
properly. Failure to disconnect the valve may disable boiler
freeze protection and result in property damage.
Approximate Time / Temperature Relationships in Scalds
120
o
F
More than 5 minutes
125
o
F
1 1/2 to 2 minutes
130
o
F
About 30 seconds
135
o
F
About 10 seconds
140
o
F
Less than 5 seconds
145
o
F
Less than 3 seconds
150
o
F
About 1 1/2 seconds
155
o
F
About 1 second
Table 3 - Time and Temperature Relationship in Scalds
Freeze Protection Operation
Stage 1
Condition
Events
Time
The water temperature
detected by probes
NTC1 or NTC2 ranges
between 39
o
F (4
o
C) and
46
o
F (8
o
C).
•
The internal pump operates at high speed.
•
The 3-Way Valve alternately switches positions - 1 minute on heating mode to
1 minute on DHW mode
•
The display shows the
icon.
Until the NTC1 and
NTC2 temperature
is greater than
or equal to
46°F
(8°C)
If after 20 minutes the conditions described in Stage 1 are still present, the boiler proceeds to Stage 2.
Stage 2
Condition
Events
Time
The water temperature
detected by probes
NTC1 or NTC2 is less
than 39
o
F (4
o
C).
•
The burner turns on at minimum power.
•
The 3-Way Valve is positioned on DHW and switches every 30 seconds
between CH and DHW.
•
When the temperature is greater than or equal to 104
o
F (40
o
C) the burner will
turn off. The boiler will maintain the temperature between 95
o
F (35
o
C) and
104
o
F (40
o
C) for 45 minutes.
•
After 45 minutes there will be 2 minutes of post heating circulation.
•
If the temperature falls below 46
o
F (8
o
C) within 150 minutes the burner will
immediately power on again.
•
The display shows the
icon.
Until the NTC1
temperature is
greater than or
equal to 104
o
F
(40
o
C)
Table 2 - Freeze Protection Detail
CAUTION
